I'm a first timer and am doing research for building a new aquarium for my 4 yr old son. I'm planning on building a well planted 75 gallon fresh water tank. I would like to have an "active" tank with 3-4 schools of fish. The two schools that my son is most insistent on are (1) Rosy Barbs (n=6-8) and Angelfish (n=6). Will these fish do well together? Are the Rosy Barbs too active for the angelfish? Is it impossible to have a school of cardinal tetras (n=10-15) with them? Thanks so much in advance for your advice.